Ethylene/α-olefin interpolymers containing low crystallinity hard blocks

ABSTRACT

The invention is related to an ethylene/α-olefin interpolymer having at least a hard segment and at least a soft segment. The soft segment contains a higher amount of comonomers than the hard segment. The hard segment has low crystallinity. The copolymer has a number of unique characteristics disclosed herein. ethylene/α-olefin interpolymers containing low crystallinity hard blocks.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.60/949,670, filed on Jul. 13, 2007, which is herein incorporated byreference in its entirety. This application is related to the followingUS applications, all filed provisionally, and concurrent with thepriority application and having Ser. No. 60/949,698; Ser. No. 60/949,690and Ser. No. 60/949,702, all of which are herein incorporated byreference.

FIELD OF THE INVENTION

This invention relates to ethylene/α-olefin interpolymers comprising lowcrystallinity hard blocks.

BACKGROUND OF THE INVENTION

Block copolymers comprise sequences (“blocks”) of the same monomer unit,covalently bound to sequences of unlike type. The blocks can beconnected in a variety of ways, such as A-B in diblock and A-B-Atriblock structures, where A represents one block and B represents adifferent block. In a multi-block copolymer, A and B can be connected ina number of different ways and be repeated multiply. It may furthercomprise additional blocks of different types. Multi-block copolymerscan be either linear multi-block or multi-block star polymers (in whichall blocks bond to the same atom or chemical moiety).

A block copolymer is created when two or more polymer molecules ofdifferent chemical composition are covalently bonded in an end-to-endfashion. While a wide variety of block copolymer architectures arepossible, most block copolymers involve the covalent bonding of hardplastic blocks, which are substantially crystalline or glassy, toelastomeric blocks forming thermoplastic elastomers. Other blockcopolymers, such as rubber-rubber (elastomer-elastomer), glass-glass,and glass-crystalline block copolymers, are also possible and may havecommercial importance.

One method to make block copolymers is to produce a “living polymer”.Unlike typical Ziegler-Natta polymerization processes, livingpolymerization processes involve only initiation and propagation stepsand essentially lack chain terminating side reactions. This permits thesynthesis of predetermined and well-controlled structures desired in ablock copolymer. A polymer created in a “living” system can have anarrow or extremely narrow distribution of molecular weight and beessentially monodisperse (i.e., the molecular weight distribution isessentially one). Living catalyst systems are characterized by aninitiation rate which is on the order of or exceeds the propagationrate, and the absence of termination or transfer reactions. In addition,these catalyst systems are characterized by the presence of a singletype of active site. To produce a high yield of block copolymer in apolymerization process, the catalyst must exhibit living characteristicsto a substantial extent.

Butadiene-isoprene block copolymers have been synthesized via anionicpolymerization using the sequential monomer addition technique. Insequential addition, a certain amount of one of the monomers iscontacted with the catalyst. Once a first such monomer has reacted tosubstantial extinction forming the first block, a certain amount of thesecond monomer or monomer species is introduced and allowed to react toform the second block. The process may be repeated using the same orother anionically polymerizable monomers. However, ethylene and otherα-olefins, such as propylene, butene, 1-octene, etc., are not directlyblock polymerizable by anionic techniques.

It would be useful to produce block copolymers which are based onethylene and α-olefins and have low crystallinity hard blocks.

SUMMARY OF INVENTION

The invention provides an ethylene/α-olefin interpolymer comprising ahard segment and a soft segment, wherein the ethylene/α-olefininterpolymer:

(a) has a Mw/Mn from about 1.7 to about 3.5;

(b) has an ethylene content in the hard segment in the range of from 60wt % to 95 wt % based on based on total monomer content in hard segment;

(c) (i) has a hard segment in an amount of at least 40%, at least onemelting point, Tm, in degrees Celsius and an amount of ethylene inweight percent, wt % C₂, wherein the numerical values of Tm and wt % C₂correspond to the relationship:90° C.≧Tm≧4.1276(wt % C ₂)−244.76; or

-   -   (ii) has a hard segment composition of less than 40%, at least        one melting point, Tm, in degrees Celsius and an amount of        ethylene in weight percent, wt % C₂, wherein the numerical        values of Tm and wt % C₂ correspond to the relationship:        80° C.≧Tm≦4.1276(wt % C ₂)−264.95; or    -   (iii) is characterized by an average block index greater than        zero and up to about 1.0 and a molecular weight distribution,        M_(w)/M_(n), greater than about 1.3; or    -   (iv) has a molecular fraction which elutes between 0° C. and        130° C. when fractionated using low temperature TREF,        characterized in that the fraction has a molar comonomer content        of at least 5 percent higher than that of a comparable random        ethylene interpolymer fraction eluting between the same        temperatures, wherein said comparable random ethylene        interpolymer has the same comonomer(s) and has a melt index,        density, and molar comonomer content (based on the whole        polymer) within 10 percent of that of the ethylene/α-olefin        interpolymer; or    -   (v) has a relationship between ethylene content in wt % and log        molecular weight such that a line plotted of ethylene content vs        log molecular weight as measured by GPC-IR has an absolute        slope, m, of equal to or less than 4; and,

(d) has a turbidity measurement of a 1.0 wt % solution of theethylene/α-olefin interpolymer in oil or a 1.5 wt % solution in dodecaneof less than or equal to that of a comparable copolymer wherein thecomparable copolymer has the same DSC enthalpy (J/g) at greater than 55°C. within ±5 J/g, and the same overall ethylene content within 10%.

The ethylene/α-olefin interpolymer can have one or any combination ofthe above characteristics.

In one embodiment, the ethylene/α-olefin interpolymer has (a) at leastone molecular fraction which elutes between 0° C. and 130° C. whenfractionated using TREF, characterized in that the fraction has a blockindex of at least 0.5 and up to about 1 and a molecular weightdistribution, Mw/Mn, greater than about 1.3 or (b) an average blockindex greater than zero and up to about 1.0 and a molecular weightdistribution, Mw/Mn, greater than about 1.3.

In one embodiment, the ethylene/α-olefin interpolymer is a random blockcopolymer comprising at least a hard block (or segment) and at least asoft block (or segment). Further, the random block copolymer cancomprise multiple hard blocks and multiple soft blocks, and the hardblocks and soft blocks can be randomly distributed in a polymeric chain.

In one embodiment, the α-olefin used in the ethylene/α-olefininterpolymer is styrene, propylene, 1-butene, 1-hexene, 1-octene,4-methyl-1-pentene, norbornene, 1-decene, 1,5-hexadiene, or acombination thereof.

In another embodiment, the ethylene/α-olefin interpolymer has a meltindex in the range of about 0.1 to about 2000 g/10 minutes, about 2 toabout 1500 g/10 minutes, about 2 to about 1000 g/10 minutes or about 2to about 500 g/10 minutes measured according to ASTM D-1238, Condition190° C./2.16 kg.

Additional aspects of the invention and characteristics and propertiesof various embodiments of the invention will become apparent with thefollowing description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a plot of T_(m) vs wt % C₂ for hard segment majoritycopolymers of the invention and for Comparative Examples.

FIG. 2 shows a plot of T_(m) vs wt % C₂ for soft segment majoritycopolymers of the invention and for Comparative Examples.

FIG. 3 shows a plot of GPC-IR data for Example 1 and Comparatives A andD.

DETAILED DESCRIPTION OF THE INVENTION General Definitions

“Polymer” means a polymeric compound prepared by polymerizing monomers,whether of the same or a different type. The generic term “polymer”embraces the terms “homopolymer,” “copolymer,” “terpolymer” as well as“interpolymer.”

“Interpolymer” means a polymer prepared by the polymerization of atleast two different types of monomers. The generic term “interpolymer”includes the term “copolymer” (which is usually employed to refer to apolymer prepared from two different monomers) as well as the term“terpolymer” (which is usually employed to refer to a polymer preparedfrom three different types of monomers). It also encompasses polymersmade by polymerizing four or more types of monomers.

The term “ethylene/α-olefin interpolymer” generally refers to polymerscomprising ethylene and an α-olefin having 3 or more carbon atoms.Preferably, ethylene comprises the majority mole fraction of the wholepolymer, i.e., ethylene comprises at least about 50 mole percent of thewhole polymer. More preferably ethylene comprises at least about 60 molepercent, at least about 70 mole percent, or at least about 80 molepercent, with the substantial remainder of the whole polymer comprisingat least one other comonomer that is preferably an α-olefin having 3 ormore carbon atoms. For many ethylene/propylene copolymers, the preferredcomposition comprises an ethylene content in the range of from about 55wt % to about 75 wt %, preferably in the range of from about 60 wt % toabout 73 wt %, based on the weight of the polymer. In some embodiments,the ethylene/α-olefin interpolymers do not include those produced in lowyields or in a minor amount or as a by-product of a chemical process.While the ethylene/α-olefin interpolymers can be blended with one ormore polymers, the as-produced ethylene/α-olefin interpolymers aresubstantially pure and often comprise a major component of the reactionproduct of a polymerization process.

The ethylene/α-olefin interpolymers comprise ethylene and one or morecopolymerizable α-olefin comonomers in polymerized form, characterizedby multiple blocks or segments of two or more polymerized monomer unitsdiffering in chemical or physical properties. That is, theethylene/α-olefin interpolymers are block interpolymers, preferablymulti-block interpolymers or copolymers. The terms “interpolymer” and“copolymer” are used interchangeably herein. In some embodiments, themulti-block copolymer can be represented by the following formula:(AB)_(n)where n is at least 1, preferably an integer greater than 1, such as 2,3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, or higher, “A”represents a hard block or segment and “B” represents a soft block orsegment. Preferably, As and Bs are linked in a substantially linearfashion, as opposed to a substantially branched or substantiallystar-shaped fashion. In other embodiments, A blocks and B blocks arerandomly distributed along the polymer chain. In other words, the blockcopolymers usually do not have a structure as follows.AAA-AA-BBB-BBIn still other embodiments, the block copolymers do not usually have athird type of block, which comprises different comonomer(s). In yetother embodiments, each of block A and block B has monomers orcomonomers substantially randomly distributed within the block. In otherwords, neither block A nor block B comprises two or more sub-segments(or sub-blocks) of distinct composition, such as a tip segment, whichhas a substantially different composition than the rest of the block.

The multi-block polymers typically comprise various amounts of “hard”and “soft” segments. “Hard” segments refer to blocks of polymerizedunits in which ethylene is present in an amount in the range of fromabout 60 wt % to about 95 wt %, and preferably in the range of fromabout 70 wt % to about 85 wt %, based on total monomer content in thehard segment. “Soft” segments, on the other hand, refer to blocks ofpolymerized units in which the comonomer content (content of monomersother than ethylene) is in the range of from about 30 wt % to about 80wt %, preferably in the range of from about 35 wt % to about 80 wt %,based on the total monomer content in the soft segment.

The soft segments can often be present in a block interpolymer fromabout 1 weight percent to about 99 weight percent of the total weight ofthe block interpolymer, preferably from about 5 weight percent to about95 weight percent, from about 10 weight percent to about 90 weightpercent, from about 15 weight percent to about 85 weight percent, fromabout 20 weight percent to about 80 weight percent, from about 25 weightpercent to about 75 weight percent, from about 30 weight percent toabout 70 weight percent, from about 35 weight percent to about 65 weightpercent, from about 40 weight percent to about 60 weight percent, orfrom about 45 weight percent to about 55 weight percent of the totalweight of the block interpolymer. Conversely, the hard segments can bepresent in similar ranges. The polymer is said to have a hard segmentmajority when the amount of hard segment present is greater than 40% anda soft segment majority when the amount of soft segment is less than60%. The soft segment weight percentage and the hard segment weightpercentage can be calculated based on data obtained from DSC or NMR.Such methods and calculations are disclosed in U.S. patent applicationSer. No. 11/376,835, US Patent Application Publication Number2006-0199930, entitled “Ethylene/α-Olefin Block Interpolymers”, filed onMar. 15, 2006, in the name of Colin L. P. Shan, Lonnie Hazlitt, et. al.and assigned to Dow Global Technologies Inc., the disclosure of which isincorporated by reference herein in its entirety.

The term “crystalline” if employed, refers to a polymer that possesses afirst order transition or crystalline melting point (Tm) as determinedby differential scanning calorimetry (DSC) or equivalent technique. Theterm may be used interchangeably with the term “semicrystalline”. Theterm “amorphous” refers to a polymer lacking a crystalline melting pointas determined by differential scanning calorimetry (DSC) or equivalenttechnique.

The term “multi-block copolymer” or “segmented copolymer” refers to apolymer comprising two or more chemically distinct regions or segments(referred to as “blocks”) preferably joined in a linear manner, that is,a polymer comprising chemically differentiated units which are joinedend-to-end with respect to polymerized ethylenic functionality, ratherthan in pendent or grafted fashion. In a preferred embodiment, theblocks differ in the amount or type of comonomer incorporated therein,the density, the amount of crystallinity, the crystallite sizeattributable to a polymer of such composition, the type or degree oftacticity (isotactic or syndiotactic), regio-regularity orregio-irregularity, the amount of branching, including long chainbranching or hyper-branching, the homogeneity, or any other chemical orphysical property. The multi-block copolymers are characterized byunique distributions of both polydispersity index (PDI or Mw/Mn), blocklength distribution, and/or block number distribution due to the uniqueprocess of making the copolymers. More specifically, when produced in acontinuous process, the polymers desirably possess PDI from 1.7 to 2.9,preferably from 1.8 to 2.5, more preferably from 1.8 to 2.2, and mostpreferably from 1.8 to 2.1. When produced in a batch or semi-batchprocess, the polymers possess PDI from 1.0 to 2.9, preferably from 1.3to 2.5, more preferably from 1.4 to 2.0, and most preferably from 1.4 to1.8.

In the following description, all numbers disclosed herein areapproximate values, regardless whether the word “about” or “approximate”is used in connection therewith. They may vary by 1 percent, 2 percent,5 percent, or, sometimes, 10 to 20 percent. Whenever a numerical rangewith a lower limit, R^(L) and an upper limit, R^(U), is disclosed, anynumber falling within the range is specifically disclosed. Inparticular, the following numbers within the range are specificallydisclosed: R=R^(L)+k*(R^(U)−R^(L)), wherein k is a variable ranging from1 percent to 100 percent with a 1 percent increment, i.e., k is 1percent, 2 percent, 3 percent, 4 percent, 5 percent, . . . , 50 percent,51 percent, 52 percent, . . . , 95 percent, 96 percent, 97 percent, 98percent, 99 percent, or 100 percent. Moreover, any numerical rangedefined by two R numbers as defined in the above is also specificallydisclosed.

Ethylene/α-olefin interpolymers containing low crystallinity hard blocksare polymers that have hard blocks that have melting points that areless than 100° C. These polymers differ from high melting point blockcopolymers in that their primary use is for compatibilization of polymerblend components and/or improving the solubility of polymers in solventsand oils. Applications include oil viscosity modifiers, thermoplasticolefin impact modifiers and compatibilizers, elastomer cross-linking andheat sealing polymers. Applications such as these require polymers witha low but broad range of temperatures for thermosetting and heat sealingoperations.

Disclosed herein is an ethylene/α-olefin interpolymer comprising a hardsegment and a soft segment, wherein the ethylene/α-olefin interpolymer:

(a) has a Mw/Mn from about 1.7 to about 3.5;

(b) has an ethylene content in the hard segment in the range of from 60wt % to 95 wt % based on based on total monomer content in hard segment;

(c) (i) has a hard segment composition of at least 40%, at least onemelting point, Tm, in degrees Celsius and an amount of ethylene inweight percent, wt % C₂, wherein the numerical values of Tm and wt % C₂correspond to the relationship:90° C.≧Tm≧4.1276(wt % C ₂)−244.76; or

-   -   (ii) has a hard segment composition of less than 40%, at least        one melting point, Tm, in degrees Celsius and an amount of        ethylene in weight percent, wt % C₂, wherein the numerical        values of Tm and wt % C₂ correspond to the relationship:        80° C.≧Tm≦4.1276(wt % C ₂)−264.95; or    -   (iii) is characterized by an average block index greater than        zero and up to about 1.0 and a molecular weight distribution,        M_(w)/M_(n), greater than about 1.3; or    -   (iv) has a molecular fraction which elutes between 0° C. and        130° C. when fractionated using low temperature TREF,        characterized in that the fraction has a molar comonomer content        of at least 5 percent higher than that of a comparable random        ethylene interpolymer fraction eluting between the same        temperatures, wherein said comparable random ethylene        interpolymer has the same comonomer(s) and has a melt index,        density, and molar comonomer content (based on the whole        polymer) within 10 percent of that of the ethylene/α-olefin        interpolymer; or    -   (v) has a relationship between ethylene content in wt % and log        molecular weight such that a line plotted of ethylene content vs        log molecular weight as measured by GPC-IR has an absolute        slope, m, of equal to or less than 4; and,

(d) has a turbidity measurement of a 1.0 wt % solution of theethylene/α-olefin interpolymer in oil or a 1.5 wt % solution in dodecaneof less than or equal to that of a comparable copolymer wherein thecomparable copolymer has the same DSC enthalpy (J/g) at greater than 55°C. within ±5 J/g, preferably ±2.5 J/g.

The ethylene/α-olefin interpolymer can have one or any combination ofthe above characteristics.

Ethylene/α-Olefin Interpolymers

The ethylene/α-olefin interpolymers used in embodiments of the invention(also referred to as “inventive interpolymer” or “inventive polymer”)comprise ethylene and one or more copolymerizable α-olefin comonomers inpolymerized form, characterized by multiple blocks or segments of two ormore polymerized monomer units differing in chemical or physicalproperties (block interpolymer), preferably a multi-block copolymer.

In some embodiments, the multi-block copolymers possess a PDI fitting aSchultz-Flory distribution rather than a Poisson distribution. Thecopolymers are further characterized as having both a polydisperse blockdistribution and a polydisperse distribution of block sizes andpossessing a most probable distribution of block lengths. Preferredmulti-block copolymers are those containing 4 or more blocks or segmentsincluding terminal blocks. More preferably, the copolymers include atleast 5, 10 or 20 blocks or segments including terminal blocks.

In one aspect, the ethylene/α-olefin interpolymers have a molecularfraction which elutes between 0° C. and 130° C. when fractionated usingTemperature Rising Elution Fractionation (“TREF”), characterized in thatsaid fraction has a molar comonomer content higher, preferably at least5 percent higher, more preferably at least 10 percent higher, than thatof a comparable random ethylene interpolymer fraction eluting betweenthe same temperatures, wherein the comparable random ethyleneinterpolymer contains the same comonomer(s), and has a melt index,density, and molar comonomer content (based on the whole polymer) within10 percent of that of the block interpolymer. Preferably, the Mw/Mn ofthe comparable interpolymer is also within 10 percent of that of theblock interpolymer and/or the comparable interpolymer has a totalcomonomer content within 10 weight percent of that of the blockinterpolymer.

Comonomer content may be measured using any suitable technique, withtechniques based on nuclear magnetic resonance (“NMR”) spectroscopypreferred. Moreover, for polymers or blends of polymers havingrelatively broad TREF curves, the polymer desirably is firstfractionated using TREF into fractions each having an eluted temperaturerange of 10° C. or less. That is, each eluted fraction has a collectiontemperature window of 10° C. or less. Using this technique, said blockinterpolymers have at least one such fraction having a higher molarcomonomer content than a corresponding fraction of the comparableinterpolymer.

In another aspect, the inventive polymer is an olefin interpolymer,preferably comprising ethylene and one or more copolymerizablecomonomers in polymerized form, characterized by multiple blocks (i.e.,at least two blocks) or segments of two or more polymerized monomerunits differing in chemical or physical properties (blockedinterpolymer), most preferably a multi-block copolymer, said blockinterpolymer having a peak (but not just a molecular fraction) whichelutes between 0° C. and 130° C. (but without collecting and/orisolating individual fractions), characterized in that said peak, has acomonomer content estimated by infra-red spectroscopy when expandedusing a full width/half maximum (FWHM) area calculation, has an averagemolar comonomer content higher, preferably at least 5 percent higher,more preferably at least 10 percent higher, than that of a comparablerandom ethylene interpolymer peak at the same elution temperature andexpanded using a full width/half maximum (FWHM) area calculation,wherein said comparable random ethylene interpolymer has the samecomonomer(s) and has a melt index, density, and molar comonomer content(based on the whole polymer) within 10 percent of that of the blockedinterpolymer. Preferably, the Mw/Mn of the comparable interpolymer isalso within 10 percent of that of the blocked interpolymer and/or thecomparable interpolymer has a total comonomer content within 10 weightpercent of that of the blocked interpolymer. The full width/half maximum(FWHM) calculation is based on the ratio of methyl to methylene responsearea [CH₃/CH₂] from the ATREF infra-red detector, wherein the tallest(highest) peak is identified from the base line, and then the FWHM areais determined. For a distribution measured using an ATREF peak, the FWHMarea is defined as the area under the curve between T₁ and T₂, where T₁and T₂ are points determined, to the left and right of the ATREF peak,by dividing the peak height by two, and then drawing a line horizontalto the base line, that intersects the left and right portions of theATREF curve. A calibration curve for comonomer content is made usingrandom ethylene/α-olefin copolymers, plotting comonomer content from NMRversus FWHM area ratio of the TREF peak. For this infra-red method, thecalibration curve is generated for the same comonomer type of interest.The comonomer content of TREF peak of the inventive polymer can bedetermined by referencing this calibration curve using its FWHMmethyl:methylene area ratio [CH₃/CH₂] of the TREF peak.

In addition to the above aspects and properties described herein, theinventive polymers can be characterized by one or more additionalcharacteristics. In one aspect, the inventive polymer is an olefininterpolymer, preferably comprising ethylene and one or morecopolymerizable comonomers in polymerized form, characterized bymultiple blocks or segments of two or more polymerized monomer unitsdiffering in chemical or physical properties (blocked interpolymer),most preferably a multi-block copolymer, said block interpolymer havinga molecular fraction which elutes between 0° C. and 130° C., whenfractionated using TREF increments, characterized in that said fractionhas a molar comonomer content higher, preferably at least 5 percenthigher, more preferably at least 10, 15, 20 or 25 percent higher, thanthat of a comparable random ethylene interpolymer fraction elutingbetween the same temperatures, wherein said comparable random ethyleneinterpolymer comprises the same comonomer(s), preferably it is the samecomonomer(s), and a melt index, density, and molar comonomer content(based on the whole polymer) within 10 percent of that of the blockedinterpolymer. Preferably, the Mw/Mn of the comparable interpolymer isalso within 10 percent of that of the blocked interpolymer and/or thecomparable interpolymer has a total comonomer content within 10 weightpercent of that of the blocked interpolymer.

In some embodiments, the ethylene/α-olefin interpolymers additionallyhave a Tm in the range of from −25° C. to 100° C., preferably from 30°C. to 80° C., and more preferably from 35° C. to 75° C. In someembodiments, they may also have a Tm in the range of from 15° C. to 50°C., from 30° C. to 45° C. or from 35° C. to 40° C. In some embodiments,the interpolymers have a Tm that is less than that of a comparablerandom copolymer with same weight percent comonomer within 10%. Inaddition, in some embodiments the end of melting occurs at less than100° C., preferably in the range of from 85° C. to 95° C.

In one aspect of the invention, the ethylene/α-olefin interpolymers havea hard segment majority and have a melting temperature that is greaterthan that of a corresponding random copolymer. In another aspect, theethylene/α-olefin interpolymers have a soft segment majority and have amelting temperature that is less than that of a corresponding randomcopolymer.

In another aspect of the invention, the ethylene/α-olefin interpolymershave a turbidity in a 1.0 wt % solution of the ethylene/α-olefininterpolymer in oil or a 1.5 wt % solution in dodecane as compared tothat of a random or a blend of polymers having the same integrated DSCenthalpy (J/g) above about 55° C. within 5 J/g, that is less than orequal to the comparative polymers within ±10%. In some aspects, theinterpolymers of the invention have such a turbidity that is less than1.5 NTU and a DSC enthalpy at greater than 55° C. of less than 2 J/g.

The ethylene/α-olefin interpolymers have a relationship between ethyleneand log molecular weight such that a line plotted of ethylene content vslog molecular weight as measured by GPC-IR has an absolute slope, m, ofequal to or less than 4. The interpolymers of the present invention alsohave an absolute slope, m, that is less than that for a blend ofpolymers with the same total weight percent ethylene, within ±20%preferably within ±10%, and more preferably within ±5%.

In one embodiment of the invention, the ethylene/α-olefin interpolymershave an integrated DSC Enthalpy (J/g) above 30° C. that is greater than7.5 J/g, have an MWD >1.7, a molecular fraction which elutes between 10°C. and 130° C., when fractionated using TREF increments, characterizedin that said fraction has a molar comonomer content higher, preferablyat least 5 percent higher, more preferably at least 10, 15, 20 or 25percent higher, than that of a comparable random ethylene interpolymerfraction eluting between the same temperatures, wherein said comparablerandom ethylene interpolymer comprises the same comonomer(s), preferablyit is the same comonomer(s), and a melt index, density, and molarcomonomer content (based on the whole polymer) within 10 percent of thatof the blocked interpolymer; and, a room temperature turbidity of a 1 wt% solution of inventive polymer in oil (Exxon FN1365 100LP Base Oil) ofless than 10 NTU, preferably less than 5 NTU, most preferably less than3 NTU.

ATREF Peak Comonomer Composition Measurement by Infra-Red Detector

The comonomer composition of the TREF peak can be measured using an IR4infra-red detector available from Polymer Char, Valencia, Spain(http://www.polymerchar.com/).

The “composition mode” of the detector is equipped with a measurementsensor (CH₂) and composition sensor (CH₃) that are fixed narrow bandinfra-red filters in the region of 2800-3000 cm⁻¹. The measurementsensor detects the methylene (CH₂) carbons on the polymer (whichdirectly relates to the polymer concentration in solution) while thecomposition sensor detects the methyl (CH₃) groups of the polymer. Themathematical ratio of the composition signal (CH₃) divided by themeasurement signal (CH₂) is sensitive to the comonomer content of themeasured polymer in solution and its response is calibrated with knownethylene alpha-olefin copolymer standards.

The detector when used with an ATREF instrument provides both aconcentration (CH₂) and composition (CH₃) signal response of the elutedpolymer during the TREF process. A polymer specific calibration can becreated by measuring the area ratio of the CH₃ to CH₂ for polymers withknown comonomer content (preferably measured by NMR). The comonomercontent of an ATREF peak of a polymer can be estimated by applying thereference calibration of the ratio of the areas for the individual CH₃and CH₂ response (i.e. area ratio CH₃/CH₂ versus comonomer content).

The area of the peaks can be calculated using a full width/half maximum(FWHM) calculation after applying the appropriate baselines to integratethe individual signal responses from the TREF chromatogram. The fullwidth/half maximum calculation is based on the ratio of methyl tomethylene response area [CH₃/CH₂] from the ATREF infra-red detector,wherein the tallest (highest) peak is identified from the base line, andthen the FWHM area is determined. For a distribution measured using anATREF peak, the FWHM area is defined as the area under the curve betweenT1 and T2, where T1 and T2 are points determined, to the left and rightof the ATREF peak, by dividing the peak height by two, and then drawinga line horizontal to the base line, that intersects the left and rightportions of the ATREF curve.

The application of infra-red spectroscopy to measure the comonomercontent of polymers in this ATREF-infra-red method is, in principle,similar to that of GPC/FTIR systems as described in the followingreferences: Markovich, Ronald P.; Hazlitt, Lonnie G.; Smith, Linley;“Development of gel-permeation chromatography-Fourier transform infraredspectroscopy for characterization of ethylene-based polyolefincopolymers”. Polymeric Materials Science and Engineering (1991), 65,98-100.; and Deslauriers, P. J.; Rohlfing, D. C.; Shieh, E. T.;“Quantifying short chain branching microstructures in ethylene-1-olefincopolymers using size exclusion chromatography and Fourier transforminfrared spectroscopy (SEC-FTIR)”, Polymer (2002), 43, 59-170, both ofwhich are incorporated by reference herein in their entirety.

In other embodiments, the inventive ethylene/α-olefin interpolymer ischaracterized by an average block index, ABI, which is greater than zeroand up to about 1.0 and a molecular weight distribution, M_(w)/M_(n),greater than about 1.3. The average block index, ABI, is the weightaverage of the block index (“BI”) for each of the polymer fractionsobtained in preparative TREF from 20° C. and 110° C., with an incrementof 5° C.:ABI=Σ(w _(i)BI_(i))

where BI_(i) is the block index for the i^(th) fraction of the inventiveethylene/α-olefin interpolymer obtained in preparative TREF, and w_(i)is the weight percentage of the i^(th) fraction.

For each polymer fraction, BI is defined by one of the two followingequations (both of which give the same BI value):

${BI} = {{\frac{{1/T_{X}} - {1/T_{XO}}}{{1/T_{A}} - {1/T_{AB}}}\mspace{14mu}{or}\mspace{14mu}{BI}} = {- \frac{{LnP}_{X} - {LnP}_{XO}}{{LnP}_{A} - {LnP}_{AB}}}}$

where T_(X) is the preparative ATREF elution temperature for the i^(th)fraction (preferably expressed in Kelvin), P_(X) is the ethylene molefraction for the i^(th) fraction, which can be measured by NMR or IR asdescribed above. P_(AB) is the ethylene mole fraction of the wholeethylene/α-olefin interpolymer (before fractionation), which also can bemeasured by NMR or IR. T_(A) and P_(A) are the ATREF elution temperatureand the ethylene mole fraction for pure “hard segments” (which refer tothe crystalline segments of the interpolymer). As a first orderapproximation, the T_(A) and P_(A) values are set to those for highdensity polyethylene homopolymer, if the actual values for the “hardsegments” are not available. For calculations performed herein, T_(A) is372° K., P_(A) is 1.

T_(AB) is the ATREF temperature for a random copolymer of the samecomposition and having an ethylene mole fraction of P_(AB). T_(AB) canbe calculated from the following equation:LnP _(AB) =α/T _(AB)+β

where α and β are two constants which can be determined by calibrationusing a number of known random ethylene copolymers. It should be notedthat α and β may vary from instrument to instrument. Moreover, one wouldneed to create their own calibration curve with the polymer compositionof interest and also in a similar molecular weight range as thefractions. There is a slight molecular weight effect. If the calibrationcurve is obtained from similar molecular weight ranges, such effectwould be essentially negligible. In some embodiments, random ethylenecopolymers satisfy the following relationship:LnP=−237.83/T _(ATREF)+0.639

T_(XO) is the ATREF temperature for a random copolymer of the samecomposition and having an ethylene mole fraction of P_(X). T_(XO) can becalculated from LnP_(X)=α/T_(XO)+β. Conversely, P_(XO) is the ethylenemole fraction for a random copolymer of the same composition and havingan ATREF temperature of T_(X), which can be calculated from LnP_(XO)=α/T_(X)+β.

Once the block index (BI) for each preparative TREF fraction isobtained, the weight average block index, ABI, for the whole polymer canbe calculated. In some embodiments, ABI is greater than zero but lessthan about 0.3 or from about 0.1 to about 0.3. In other embodiments, ABIis greater than about 0.3 and up to about 1.0. Preferably, ABI should bein the range of from about 0.4 to about 0.7, from about 0.5 to about0.7, or from about 0.6 to about 0.9. In some embodiments, ABI is in therange of from about 0.3 to about 0.9, from about 0.3 to about 0.8, orfrom about 0.3 to about 0.7, from about 0.3 to about 0.6, from about 0.3to about 0.5, or from about 0.3 to about 0.4. In other embodiments, ABIis in the range of from about 0.4 to about 1.0, from about 0.5 to about1.0, or from about 0.6 to about 1.0, from about 0.7 to about 1.0, fromabout 0.8 to about 1.0, or from about 0.9 to about 1.0.

Another characteristic of the inventive ethylene/α-olefin interpolymeris that the inventive ethylene/α-olefin interpolymer comprises at leastone polymer fraction which can be obtained by preparative TREF, whereinthe fraction has a block index greater than about 0.1 and up to about1.0 and a molecular weight distribution, M_(w)/M_(n), greater than about1.3. In some embodiments, the polymer fraction has a block index greaterthan about 0.6 and up to about 1.0, greater than about 0.7 and up toabout 1.0, greater than about 0.8 and up to about 1.0, or greater thanabout 0.9 and up to about 1.0. In other embodiments, the polymerfraction has a block index greater than about 0.1 and up to about 1.0,greater than about 0.2 and up to about 1.0, greater than about 0.3 andup to about 1.0, greater than about 0.4 and up to about 1.0, or greaterthan about 0.4 and up to about 1.0. In still other embodiments, thepolymer fraction has a block index greater than about 0.1 and up toabout 0.5, greater than about 0.2 and up to about 0.5, greater thanabout 0.3 and up to about 0.5, or greater than about 0.4 and up to about0.5. In yet other embodiments, the polymer fraction has a block indexgreater than about 0.2 and up to about 0.9, greater than about 0.3 andup to about 0.8, greater than about 0.4 and up to about 0.7, or greaterthan about 0.5 and up to about 0.6.

For copolymers of ethylene and an α-olefin, the inventive polymerspreferably possess (1) a PDI of at least 1.3, more preferably at least1.5, at least 1.7, or at least 2.0, and most preferably at least 2.6, upto a maximum value of 5.0, more preferably up to a maximum of 3.5, andespecially up to a maximum of 2.7; (2) a heat of fusion of 80 J/g orless; (3) an ethylene content of at least 50 weight percent; (4) a glasstransition temperature, T_(g), of less than −25° C., more preferablyless than −30° C., and/or (5) one and only one T_(m).

Additionally, the ethylene/α-olefin interpolymers can have a melt index,I₂, from 0.01 to 2000 g/10 minutes, preferably from 0.01 to 1000 g/10minutes, more preferably from 0.01 to 500 g/10 minutes, and especiallyfrom 0.01 to 100 g/10 minutes. In certain embodiments, theethylene/α-olefin interpolymers have a melt index, I₂, from 0.01 to 10g/10 minutes, from 0.5 to 50 g/10 minutes, from 1 to 30 g/10 minutes,from 1 to 6 g/10 minutes or from 0.3 to 10 g/10 minutes. In certainembodiments, the melt index for the ethylene/α-olefin polymers is 1 g/10minutes, 3 g/10 minutes or 5 g/10 minutes.

The polymers can have molecular weights, M_(w), from 1,000 g/mole to5,000,000 g/mole, preferably from 1000 g/mole to 1,000,000, morepreferably from 10,000 g/mole to 500,000 g/mole, and especially from10,000 g/mole to 300,000 g/mole. The density of the inventive polymerscan be from 0.80 to 0.99 g/cm³ and preferably for ethylene containingpolymers from 0.85 g/cm³ to 0.97 g/cm³. In certain embodiments, thedensity of the ethylene/α-olefin polymers ranges from 0.860 to 0.925g/cm³ or 0.867 to 0.910 g/cm³.

Processes useful for making the polymers have been disclosed in thefollowing patent applications: U.S. Provisional Application No.60/553,906, filed Mar. 17, 2004; U.S. Provisional Application No.60/662,937, filed Mar. 17, 2005; U.S. Provisional Application No.60/662,939, filed Mar. 17, 2005; U.S. Provisional Application No.60/566,2938, filed Mar. 17, 2005; PCT Application No. PCT/US2005/008916,filed Mar. 17, 2005, publication number WO 2005/090425, published Sep.29, 2005; PCT Application No. PCT/US2005/008915, filed Mar. 17, 2005,publication number WO 2005/090426, published Sep. 29, 2005; and PCTApplication No. PCT/US2005/008917, filed Mar. 17, 2005, publicationnumber WO 2005/090427, published Sep. 29, 2005 all of which areincorporated by reference herein in their entirety. For example, onesuch method comprises contacting ethylene and optionally one or moreaddition polymerizable monomers other than ethylene under additionpolymerization conditions with a catalyst composition comprising:

the admixture or reaction product resulting from combining:

(A) a first olefin polymerization catalyst having a high comonomerincorporation index,

(B) a second olefin polymerization catalyst having a comonomerincorporation index less than 90 percent, preferably less than 50percent, most preferably less than 5 percent of the comonomerincorporation index of catalyst (A), and

(C) a chain shuttling agent.

Representative catalysts and chain shuttling agent are as follows.Chemical structures follow each description.

Catalyst (A1) is[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl, prepared according to the teachings of WO 03/40195,2003US0204017, U.S. Ser. No. 10/429,024, filed May 2, 2003, and WO04/24740, all of which are herein incorporated by reference.

Catalyst (A2) is[N-(2,6-di(1-methylethyl)phenyl)amido)(2-methylphenyl)(1,2-phenylene-(6-pyridin-2-diyl)methane)]hafniumdimethyl, prepared according to the teachings of WO 03/40195,2003US0204017, U.S. Ser. No. 10/429,024, filed May 2, 2003, and WO04/24740, all of which are herein incorporated by reference.

Catalyst (A3) is bis[N,N′″-(2,4,6tri(methylphenyl)amido)ethylenediamine]hafnium dibenzyl.

Catalyst (A4) isbis((2-oxoyl-3-(dibenzo-1H-pyrrole-1-yl)-5-(methyl)phenyl)-2-phenoxymethyl)cyclohexane-1,2-diylzirconium (IV) dibenzyl, prepared substantially according to theteachings of US-A-2004/0010103, which is herein incorporated byreference.

Catalyst (A5) is[η²-2,6-diisopropyl-N-(2-methyl-3-(octylimino)butan-2-yl)benzenamide]trimethylhafnium,prepared substantially according to the teachings of WO2003/051935,which is herein incorporated by reference.

Catalyst (B1) is1,2-bis-(3,5-di-t-butylphenylene)(1-(N-(1-methylethyl)imino)methyl)(2-oxoyl)zirconium dibenzyl

Catalyst (B2) is1,2-bis-(3,5-di-t-butylphenylene)(1-(N-(2-methylcyclohexyl)-immino)methyl)(2-oxoyl)zirconium dibenzyl

Catalyst (C1) is(t-butylamido)dimethyl(3-N-pyrrolyl-1,2,3,3a,7a-η-inden-1-yl)silanetitaniumdimethyl prepared substantially according to the techniques of U.S. Pat.No. 6,268,444, which is herein incorporated by reference:

Catalyst (C2) is(t-butylamido)di(4-methylphenyl)(2-methyl-1,2,3,3a,7a-η-inden-1-yl)silanetitaniumdimethyl prepared substantially according to the teachings ofUS-A-2003/004286, which is herein incorporated by reference:

Catalyst (C3) is(t-butylamido)di(4-methylphenyl)(2-methyl-1,2,3,3a,8a-η-s-indacen-1-yl)silanetitaniumdimethyl prepared substantially according to the teachings ofUS-A-2003/004286, which is herein incorporated by reference:

Catalyst (D1) is bis(dimethyldisiloxane)(indene-1-yl)zirconiumdichloride available from Sigma-Aldrich:

Shuttling Agents The shuttling agents employed include diethylzinc,di(i-butyl)zinc, di(n-hexyl)zinc, triethylaluminum, trioctylaluminum,triethylgallium, i-butylaluminum bis(dimethyl(t-butyl)siloxane),i-butylaluminum bis(di(trimethylsilyl)amide), n-octylaluminumdi(pyridine-2-methoxide), bis(n-octadecyl)i-butylaluminum,i-butylaluminum bis(di(n-pentyl)amide), n-octylaluminumbis(2,6-di-t-butylphenoxide, n-octylaluminum di(ethyl(1-naphthyl)amide),ethylaluminum bis(t-butyldimethylsiloxide), ethylaluminumdi(bis(trimethylsilyl)amide), ethylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide), n-octylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide), n-octylaluminumbis(dimethyl(t-butyl)siloxide, ethylzinc(2,6-diphenylphenoxide), andethylzinc (t-butoxide).

Preferably, the foregoing process takes the form of a continuoussolution process for forming block copolymers, especially multi-blockcopolymers, preferably linear multi-block copolymers of two or moremonomers, more especially ethylene and a C₃₋₂₀ olefin or cycloolefin,and most especially ethylene and a C₄₋₂₀ α-olefin, using multiplecatalysts that are incapable of interconversion. That is, the catalystsare chemically distinct. Under continuous solution polymerizationconditions, the process is ideally suited for polymerization of mixturesof monomers at high monomer conversions. Under these polymerizationconditions, shuttling from the chain shuttling agent to the catalystbecomes advantaged compared to chain growth, and multi-block copolymers,especially linear multi-block copolymers are formed in high efficiency.Chain terminating agents such as hydrogen may be used if desired tocontrol reactor viscosity or polymer molecular weight.

The inventive interpolymers may comprise alternating blocks of differingcomonomer content (including homopolymer blocks). The inventiveinterpolymers may also comprise a distribution in number and/or blocksize of polymer blocks of differing density or comonomer content, whichis a Schultz-Flory type of distribution.

Moreover, the inventive multiblock interpolymers may be prepared usingtechniques to influence the degree or level of blockiness. That is theamount of comonomer and length of each polymer block or segment can bealtered by controlling the ratio and type of catalysts and shuttlingagent as well as the temperature of the polymerization, and otherpolymerization variables. A surprising benefit of this phenomenon is thediscovery that as the degree of blockiness is increased, the opticalproperties, solubility of the polymer in solvents and oils, andcompatibility between dissimilar polymers are improved. In particular,haze decreases while clarity, increase as the average number of blocksin the polymer increases. By selecting shuttling agents and catalystcombinations having the desired chain transferring ability (high ratesof shuttling with low levels of chain termination) other forms ofpolymer termination are effectively suppressed. Accordingly, little ifany β-hydride elimination is observed in the polymerization ofethylene/α-olefin comonomer mixtures according to embodiments of theinvention, and the resulting crystalline blocks are highly, orsubstantially completely, linear, possessing little or no long chainbranching.

Polymers with highly crystalline chain ends can be selectively preparedin accordance with embodiments of the invention. In elastomerapplications, reducing the relative quantity of polymer that terminateswith an amorphous block reduces the intermolecular dilutive effect oncrystalline regions. This result can be obtained by choosing chainshuttling agents and catalysts having an appropriate response tohydrogen or other chain terminating agents. Specifically, if thecatalyst which produces highly crystalline polymer is more susceptibleto chain termination (such as by use of hydrogen) than the catalystresponsible for producing the less crystalline polymer segment (such asthrough higher comonomer incorporation, regio-error, or atactic polymerformation), then the highly crystalline polymer segments willpreferentially populate the terminal portions of the polymer. Not onlyare the resulting terminated groups crystalline, but upon termination,the highly crystalline polymer forming catalyst site is once againavailable for reinitiation of polymer formation. The initially formedpolymer is therefore another highly crystalline polymer segment.Accordingly, both ends of the resulting multi-block copolymer arepreferentially highly crystalline.

The ethylene/α-olefin interpolymers used in the embodiments of theinvention are preferably interpolymers of ethylene with at least oneC₃-C₂₀ α-olefin. Copolymers of ethylene and a C₃-C₂₀ α-olefin areespecially preferred. The interpolymers may further comprise C₄-C₁₈diolefin and/or alkenylbenzene. Suitable unsaturated comonomers usefulfor polymerizing with ethylene include, for example, ethylenicallyunsaturated monomers, conjugated or nonconjugated dienes, polyenes,alkenylbenzenes, etc. Examples of such comonomers include C₃-C₂₀α-olefins such as propylene, isobutylene, 1-butene, 1-hexene, 1-pentene,4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, and thelike. Propylene and non-conjugated dienes are preferred. Other suitablemonomers include styrene, halo- or alkyl-substituted styrenes,vinylbenzocyclobutane, 1,4-hexadiene, 1,7-octadiene, and naphthenics(e.g., cyclopentene, cyclohexene and cyclooctene).

While ethylene/α-olefin interpolymers are preferred polymers, otherethylene/olefin polymers may also be used. Olefins as used herein referto a family of unsaturated hydrocarbon-based compounds with at least onecarbon-carbon double bond. Depending on the selection of catalysts, anyolefin may be used in embodiments of the invention. Preferably, suitableolefins are C₃-C₂₀ aliphatic and aromatic compounds containing vinylicunsaturation, as well as cyclic compounds, such as cyclobutene,cyclopentene, dicyclopentadiene, and norbornene, including but notlimited to, norbornene substituted in the 5 and 6 position with C₁-C₂₀hydrocarbyl or cyclohydrocarbyl groups. Also included are mixtures ofsuch olefins as well as mixtures of such olefins with C₄-C₄₀ diolefincompounds.

Examples of olefin monomers include, but are not limited to propylene,isobutylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene,1-nonene, 1-decene, and 1-dodecene, 1-tetradecene, 1-hexadecene,1-octadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene,4-methyl-1-pentene, 4,6-dimethyl-1-heptene, 4-vinylcyclohexene,vinylcyclohexane, norbornadiene, ethylidene norbornene, cyclopentene,cyclohexene, dicyclopentadiene, cyclooctene, C₄-C₄₀ dienes, includingbut not limited to 1,3-butadiene, 1,3-pentadiene, 1,4-hexadiene,1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, other C₄-C₄₀ α-olefins, andthe like. In certain embodiments, the α-olefin is propylene, 1-butene,1-pentene, 1-hexene, 1-octene or a combination thereof. Although anyhydrocarbon containing a vinyl group potentially may be used inembodiments of the invention, practical issues such as monomeravailability, cost, and the ability to conveniently remove unreactedmonomer from the resulting polymer may become more problematic as themolecular weight of the monomer becomes too high.

The polymerization processes described herein are well suited for theproduction of olefin polymers comprising monovinylidene aromaticmonomers including styrene, o-methyl styrene, p-methyl styrene,t-butylstyrene, and the like. In particular, interpolymers comprisingethylene and styrene can be prepared by following the teachings herein.Optionally, copolymers comprising ethylene, styrene and a C₃-C₂₀ alphaolefin, optionally comprising a C₄-C₂₀ diene, having improved propertiescan be prepared.

Suitable non-conjugated diene monomers can be a straight chain, branchedchain or cyclic hydrocarbon diene having from 6 to 15 carbon atoms.Examples of suitable non-conjugated dienes include, but are not limitedto, straight chain acyclic dienes, such as 1,4-hexadiene, 1,6-octadiene,1,7-octadiene, 1,9-decadiene, branched chain acyclic dienes, such as5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene;3,7-dimethyl-1,7-octadiene and mixed isomers of dihydromyricene anddihydroocinene, single ring alicyclic dienes, such as1,3-cyclopentadiene; 1,4-cyclohexadiene; 1,5-cyclooctadiene and1,5-cyclododecadiene, and multi-ring alicyclic fused and bridged ringdienes, such as tetrahydroindene, methyl tetrahydroindene,dicyclopentadiene, bicyclo-(2,2,1)-hepta-2,5-diene; alkenyl, alkylidene,cycloalkenyl and cycloalkylidene norbornenes, such as5-methylene-2-norbornene (MNB); 5-propenyl-2-norbornene,5-isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2-norbornene,5-cyclohexylidene-2-norbornene, 5-vinyl-2-norbornene, and norbornadiene.Of the dienes typically used to prepare EPDMs, the particularlypreferred dienes are 1,4-hexadiene (HD), 5-ethylidene-2-norbornene(ENB), 5-vinylidene-2-norbornene (VNB), 5-methylene-2-norbornene (MNB),and dicyclopentadiene (DCPD). The especially preferred dienes are5-ethylidene-2-norbornene (ENB) and 1,4-hexadiene (HD).

One class of desirable polymers that can be made in accordance withembodiments of the invention are elastomeric interpolymers of ethylene,a C₃-C₂₀ α-olefin, especially propylene, and optionally one or morediene monomers. Preferred α-olefins for use in this embodiment of thepresent invention are designated by the formula CH₂═CHR*, where R* is alinear or branched alkyl group of from 1 to 12 carbon atoms. Examples ofsuitable α-olefins include, but are not limited to, propylene,isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and1-octene. A particularly preferred α-olefin is propylene. The propylenebased polymers are generally referred to in the art as EP or EPDMpolymers. Suitable dienes for use in preparing such polymers, especiallymulti-block EPDM type polymers include conjugated or non-conjugated,straight or branched chain-, cyclic- or polycyclic-dienes comprisingfrom 4 to 20 carbons. Preferred dienes include 1,4-pentadiene,1,4-hexadiene, 5-ethylidene-2-norbornene, dicyclopentadiene,cyclohexadiene, and 5-butylidene-2-norbornene. A particularly preferreddiene is 5-ethylidene-2-norbornene.

Because the diene containing polymers comprise alternating segments orblocks containing greater or lesser quantities of the diene (includingnone) and α-olefin (including none), the total quantity of diene andα-olefin may be reduced without loss of subsequent polymer properties.That is, because the diene and α-olefin monomers are preferentiallyincorporated into one type of block of the polymer rather than uniformlyor randomly throughout the polymer, they are more efficiently utilizedand subsequently the crosslink density of the polymer can be bettercontrolled. Such crosslinkable elastomers and the cured products haveadvantaged properties, including higher tensile strength and betterelastic recovery.

In some embodiments, the inventive interpolymers made with two catalystsincorporating differing quantities of comonomer have a weight ratio ofblocks formed thereby from 95:5 to 5:95. The elastomeric polymersdesirably have an ethylene content of from 20 to 90 percent, a dienecontent of from 0.1 to 10 percent, and an α-olefin content of from 10 to80 percent, based on the total weight of the polymer. Furtherpreferably, the multi-block elastomeric polymers have an ethylenecontent of from 60 to 90 percent, a diene content of from 0.1 to 10percent, and an α-olefin content of from 10 to 40 percent, based on thetotal weight of the polymer. Preferred polymers are high molecularweight polymers, having a weight average molecular weight (Mw) from10,000 to about 2,500,000, preferably from 20,000 to 500,000, morepreferably from 20,000 to 350,000, and a polydispersity less than 3.5,more preferably less than 3.0, and a Mooney viscosity (ML (1+4) 125° C.)from 1 to 250. More preferably, such polymers have an ethylene contentfrom 65 to 75 percent, a diene content from 0 to 6 percent, and anα-olefin content from 20 to 35 percent.

The ethylene/α-olefin interpolymers can be functionalized byincorporating at least one functional group in its polymer structure.Exemplary functional groups may include, for example, ethylenicallyunsaturated mono- and di-functional carboxylic acids, ethylenicallyunsaturated mono- and di-functional carboxylic acid anhydrides, saltsthereof and esters thereof. Such functional groups may be grafted to anethylene/α-olefin interpolymer, or it may be copolymerized with ethyleneand an optional additional comonomer to form an interpolymer ofethylene, the functional comonomer and optionally other comonomer(s).Means for grafting functional groups onto polyethylene are described forexample in U.S. Pat. Nos. 4,762,890, 4,927,888, and 4,950,541, thedisclosures of these patents are incorporated herein by reference intheir entirety. One particularly useful functional group is malicanhydride.

The amount of the functional group present in the functionalinterpolymer can vary. The functional group can typically be present ina copolymer-type functionalized interpolymer in an amount of at leastabout 1.0 weight percent, preferably at least about 5 weight percent,and more preferably at least about 7 weight percent. The functionalgroup will typically be present in a copolymer-type functionalizedinterpolymer in an amount less than about 40 weight percent, preferablyless than about 30 weight percent, and more preferably less than about25 weight percent.

The ethylene/α-olefin interpolymers of the present invention may be usedin a number of applications, a non-limiting set of examples of which aregiven below. The interpolymers may be used an impact modifier forpolypropylene; a compatibilizer for random ethylene/alpha olefincopolymers or termonomers and polypropylene; and, the interpolymers maybe used as a peroxide crosslinked elastomer with either ethylene/alphaolefin copolymers or ethylene/alpha olefin/nonconjugated dienetermonomers. Additionally, the lower melting point allows formanufacture in standard thermoset applications. Such applicationsinclude, but are not limited to: conveyor belting; V-belting;crosslinked foams, including, but not limited to, midsole foams infootwear, foamed mats, wet suits, extruded sponge profiles, dualhardness sponge/solid coextruded profiles, single ply roofing, andwindshield wipers.

For an ethylene/alpha olefin/nonconjugated diene termonomer composition,sulfur or phenolic cured versions of elastomeric compositions may beproduced. Similar applications may be used as described for peroxidecrosslinked elastomers.

The compositions of the present invention may also be used in oilextended gel compounds in thermoplastic or thermoset applications. Inaddition, the ethylene/α-olefin interpolymers of the present inventionmay be used in noise, vibration and harshness (NVH) control relatedapplications.

The ethylene/α-olefin interpolymers may also comprise additives andadjuvants. Suitable additives include, but are not limited to, fillers,such as organic or inorganic particles, including clays, talc, titaniumdioxide, zeolites, powdered metals, organic or inorganic fibers,nano-sized particles, clays, and so forth; tackifiers, oil extenders,including paraffinic or napthelenic oils; and other natural andsynthetic polymers, including other polymers according to embodiments ofthe invention. Additionally, minor amounts of a different polymer may beused as a carrier for any of the additives. An example of such a polymerwould be polyethylene, for example AFFINITY® resins (The Dow ChemicalCompany) or EXACT® resins (ExxonMobil Chemical Company.

The following examples are presented to exemplify embodiments of theinvention but are not intended to limit the invention to the specificembodiments set forth. Unless indicated to the contrary, all parts andpercentages are by weight. All numerical values are approximate. Whennumerical ranges are given, it should be understood that embodimentsoutside the stated ranges may still fall within the scope of theinvention. Specific details described in each example should not beconstrued as necessary features of the invention.

EXAMPLES Testing Methods

In the examples that follow, the following analytical techniques areemployed:

GPC-IR Method

Gel Permeation Chromatography (GPC)

The gel permeation chromatographic system is either a Polymer

Laboratories Model PL-210 or a Polymer Laboratories Model PL-220instrument. The column and carousel compartments are operated at 150° C.Four Polymer Laboratories 20-micron Mixed-A columns are used. Thesolvent is 1,2,4 trichlorobenzene. The samples are prepared at aconcentration of 0.1 grams of polymer in 50 milliliters of solventcontaining 200 ppm of butylated hydroxytoluene (BHT). Samples areprepared by agitating lightly for 2 hours at 160° C. The injectionvolume used is 200 microliters and the flow rate is 1.0 ml/minute.

Calibration of the GPC column set is performed with 21 narrow molecularweight distribution polystyrene standards with molecular weights rangingfrom 580 to 8,400,000, arranged in 6 “cocktail” mixtures with at least adecade of separation between individual molecular weights. The standardsare purchased from Polymer Laboratories (Shropshire, UK). Thepolystyrene standards are prepared at 0.025 grams in 50 milliliters ofsolvent for molecular weights equal to or greater than 1,000,000, and0.05 grams in 50 milliliters of solvent for molecular weights less than1,000,000. The polystyrene standards are dissolved at 80° C. with gentleagitation for 30 minutes. The narrow standards mixtures are run firstand in order of decreasing highest molecular weight component tominimize degradation. The polystyrene standard peak molecular weightsare converted to polyethylene molecular weights using the followingequation (as described in Williams and Ward, J. Polym. Sci., Polym.Let., 6, 621 (1968)): M_(polyethylene)=0.431(M_(polystyrene)).

Polyetheylene equivalent molecular weight calculations are performedusing Viscotek TriSEC software Version 3.0.

Molecular Weight-Comonomer Composition Measurement by Infra-Red Detector

The comonomer composition throughout the GPC curve can be measured usingan IR4 infra-red detector that is available from Polymer Char, Valencia,Spain (http://www.polymerchar.com/).

The “composition mode” of the detector is equipped with a measurementsensor (CH₂) and composition sensor (CH₃) that are fixed narrow bandinfra-red filters in the region of 2800-3000 cm⁻¹. The measurementsensor detects the methylene (CH₂) carbons on the polymer (whichdirectly relates to the polymer concentration in solution) while thecomposition sensor detects the methyl (CH₃) groups of the polymer. Themathematical ratio of the composition signal (CH₃) divided by themeasurement signal (CH₂) is sensitive to the comonomer content of themeasured polymer in solution and its response is calibrated with knownethylene alpha-olefin copolymer standards.

The detector when used with a GPC instrument provides both aconcentration (CH₂) and composition (CH₃) signal response of the elutedpolymer during the GPC process. A polymer specific calibration can becreated by measuring the area ratio of the CH₃ to CH₂ for polymers withknown comonomer content (preferably measured by NMR). The comonomerdistribution of a polymer can be estimated by applying a referencecalibration of the ratio of the areas for the individual CH₃ and CH₂response (i.e. area ratio CH₃/CH₂ versus comonomer content).

By taking the ratio of the CH₃/CH₂ response at each elution volume, theresponse to the polymer's composition is measured. After applying theappropriate reference calibration, the composition response can be usedto estimate the comonomer amount at each elution volume. Integration ofthe entire GPC profile provides the average comonomer content of thepolymer while the slope of the line from the comonomer versus molecularweight provides an indication of the uniformity of the comonomerdistribution. When integrating the GPC chromatograph for compositiondetermination, the integration region should be set to be greater than 5weight percent of the polymer on either end of the chromatogram.

The application of infra-red spectroscopy to measure the comonomercontent of polymers in this system is similar in principle to GPC/FTIRsystems as described in the following references:

Markovich, Ronald P.; Hazlitt, Lonnie G.; Smith, Linley; “Development ofgel-permeation chromatography-Fourier transform infrared spectroscopyfor characterization of ethylene-based polyolefin copolymers”, PolymericMaterials Science and Engineering (1991), 65, 98-100.

Deslauriers, P. J.; Rohlfing, D. C.; Shieh, E. T.; “Quantifying shortchain branching microstructures in ethylene-1-olefin copolymers usingsize exclusion chromatography and Fourier transform infraredspectroscopy (SEC-FTIR)”, Polymer (2002), 43, 59-170.

DSC Standard Method

Differential Scanning Calorimetry results are determined using a TAImodel Q1000 DSC equipped with an RCS cooling accessory and anautosampler. A nitrogen purge gas flow of 50 ml/min is used. The sampleis pressed into a thin film and melted in the press at about 175° C. andthen air-cooled to room temperature (25° C.). 3-10 mg of material isthen cut into a 6 mm diameter disk, accurately weighed, placed in alight aluminum pan (ca 50 mg), and then crimped shut. The thermalbehavior of the sample is investigated with the following temperatureprofile. The sample is rapidly heated to 180° C. and held isothermal for3 minutes in order to remove any previous thermal history. The sample isthen cooled to −40° C. at 10° C./min cooling rate and held at −90° C.for 3 minutes. The sample is then heated to 180° C. at 10° C./min.heating rate. The cooling and second heating curves are recorded.

The DSC melting peak is measured as the maximum in heat flow rate (W/g)with respect to the linear baseline drawn between −30° C. and end ofmelting. The heat of fusion is measured as the area under the meltingcurve between −30° C. and the end of melting using a linear baseline.

Density

Samples for density measurement are prepared according to ASTM D 1928.Measurements are made within one hour of sample pressing using ASTMD792, Method B.

Melt Index

Melt index, or I₂, is measured in accordance with ASTM D 1238, Condition190° C./2.16 kg. Melt index, or I₁₀ is also measured in accordance withASTM D 1238, Condition 190° C./10 kg.

Mooney Viscosity

Mooney viscosity is measured in accordance with ASTM D1646-06 at 125°C., ML 1+4 (MU)).

ATREF

Analytical temperature rising elution fractionation (ATREF) analysis isconducted according to the method described in U.S. Pat. No. 4,798,081and Wilde, L.; Ryle, T. R.; Knobeloch, D. C.; Peat, I. R.; Determinationof Branching Distributions in Polyethylene and Ethylene Copolymers, J.Polym. Sci., 20, 441-455 (1982), which are incorporated by referenceherein in their entirety. The composition to be analyzed is dissolved inortho-dichlorobenzene and allowed to crystallize in a column containingan inert support (stainless steel shot) by slowly reducing thetemperature to −10° C. at a cooling rate of 0.1° C./min. The column isequipped with an infrared detector. An ATREF chromatogram curve is thengenerated by eluting the crystallized polymer sample from the column byslowly increasing the temperature of the eluting solvent(ortho-dichlorobenzene) from −10 to 130° C. at a rate of 1.5° C./min.

¹³C NMR Analysis

The samples are prepared by adding approximately 3 g of a 50/50 mixtureof tetrachloroethane-d²/orthodichlorobenzene to 0.4 g sample in a 10 mmNMR tube. The samples are dissolved and homogenized by heating the tubeand its contents to 150° C. The data are collected using a JEOL Eclipse™400 MHz spectrometer or a Varian Unity Plus™ 400 MHz spectrometer,corresponding to a ¹³C resonance frequency of 100.5 MHz. The data areacquired using 4000 transients per data file with a 6 second pulserepetition delay. To achieve minimum signal-to-noise for quantitativeanalysis, multiple data files are added together. The spectral width is25,000 Hz with a minimum file size of 32K data points. The samples areanalyzed at 130° C. in a 10 mm broad band probe. The comonomerincorporation is determined using Randall's triad method (Randall, J.C.; JMS-Rev. Macromol. Chem. Phys., C29, 201-317 (1989), which isincorporated by reference herein in its entirety.

Polymer Fractionation by TREF

Large-scale TREF fractionation is carried by dissolving 15-20 g ofpolymer in 2 liters of ortho-dichlorobenzene by stirring for 4 hours at160° C. The polymer solution is forced by 15 psig (100 kPa) nitrogenonto a 3 inch by 4 foot (7.6 cm×12 cm) steel column packed with a 60:40(v:v) mix of 30-40 mesh (600-425 μm) spherical, technical quality glassbeads (available from Potters Industries, HC 30 Box 20, Brownwood, Tex.,76801) and stainless steel, 0.028″ (0.7 mm) diameter cut wire shot(available from Pellets, Inc. 63 Industrial Drive, North Tonawanda,N.Y., 14120). The column is immersed in a thermally controlled oiljacket, set initially to 160° C. The column is first cooledballistically to 125° C., then slow cooled to −10° C. at 0.04° C. perminute and held for one hour. Fresh ortho-dichlorobenzene is introducedat about 65 ml/min while the temperature is increased at 0.167° C. perminute.

Approximately 2000 ml portions of eluant from the preparative TREFcolumn are collected in a 16 station, heated fraction collector. Thepolymer is concentrated in each fraction using a rotary evaporator untilabout 50 to 100 ml of the polymer solution remains. The concentratedsolutions are allowed to stand overnight before adding excess methanol,filtering, and rinsing (approx. 300-500 ml of methanol including thefinal rinse). The filtration step is performed on a 3 position vacuumassisted filtering station using 5.0 μm polytetrafluoroethylene coatedfilter paper (available from Osmonics Inc., Cat# Z50WP04750). Thefiltrated fractions are dried overnight in a vacuum oven at 60° C. andweighed on an analytical balance before further testing.

Turbidity

Turbidity of the oil or solvent solutions were measured using a HACHRATIO Turbidimeter Model 18900 using the 0-20 NTU resolution scale(+/−0.1 NTU).

Methods for Targeting the Composition in Inventive Examples

The block architecture of the inventive copolymers may be controlled bythe proper selection of catalysts to produce the desired comonomercontent in each of the segments at the reactor conditions. The amount ofcomonomer incorporated into each segment type may be predicted byindependently performing polymerization tests employing singlecatalysts. Thus, using the case of an ethylene/propylene copolymer, theratio of propylene to ethylene concentrations in the reactor ([C₃]/[C₂])determines the amount of propylene (relative to ethylene) incorporatedby each catalyst. Upon introduction of the chain shuttling agent, a‘blocky’ structure is produced by statistical coupling of the polymersegments produced by each catalyst type. The total comonomerincorporated into the polymer is then controlled by the ratio ofcatalyst A₁ to catalyst A₂. This concept of production and methodologyis explained in Arriola et al., “Catalytic Production of Olefin BlockCopolymers via Chain Shuttling Polymerization”, Science, 312 (2006).

From the above methodology, the wt % ethylene or propylene incorporatedinto the polymer by catalyst A1, the wt % ethylene or propyleneincorporated into the polymer by catalyst A2, and the amount of polymerproduced by each of the catalysts can be estimated from the reactorconditions and the overall comonomer content of the polymer.

The total/overall monomer or comonomer incorporated into the polymer canbe estimated as follows:Overall Comonomer Incorporated=M _(Overall) =X _(A) M _(A) +X _(B) M_(B)

Where

M_(Overall)=Overall wt % C₂ incorporated in whole polymer

M_(A)=wt % C₂ incorporated in segment by Catalyst A1

M_(B)=wt % C₂ incorporated in segment by Catalyst A2

X_(A)=weight fraction of segment produced by Catalyst A1

X_(B)=weight fraction of segment produced by Catalyst A2

Note: X_(A)+X_(B)=1

Using the total monomer or comonomer incorporated into the polymer asmeasured by FTIR or NMR, and knowing the comonomer concentration of eachsegment type in the reactor at the time of production, the weightfraction of polymer produced by each catalyst can be determined:Weight fraction of segment produced by Catalyst A1

$X_{A} = \frac{M_{Overall} - M_{B}}{M_{A} - M_{B}}$Weight fraction of segment produced by Catalyst A2 X_(B)=1−X_(A)Other analytical methods to confirm the composition of the segmentsinclude but are not necessarily limited to DSC, NMR, and the subsequentanalysis of polymer fractions obtained by polymer fractionation(temperature fractionation, solvent fractionation, molecular weightfractionation). Additionally, a technique such as high temperatureliquid chromatography as described in Albrecht et al. “Separation andCharacterization of Ethylene-Propylene Copolymers by High-TemperatureGradient HPLC Coupled to FTIR Spectroscopy”, Macromol. Symp., 257, 46-55(2007) could also be used. For any of these methods, the composition ofthe exemplary block copolymers may be estimated with the appropriatecalibrations based on the random copolymers produced by a similarcatalyst system and within the same range of molecular weights andoverall compositions.Catalysts

The term “overnight”, if used, refers to a time of approximately 16-18hours, the term “room temperature”, refers to a temperature of 20-25°C., and the term “mixed alkanes” refers to a commercially obtainedmixture of C₆₋₉ aliphatic hydrocarbons available under the tradedesignation Isopar E®, from ExxonMobil Chemical Company. In the eventthe name of a compound herein does not conform to the structuralrepresentation thereof, the structural representation shall control. Thesynthesis of all metal complexes and the preparation of all screeningexperiments were carried out in a dry nitrogen atmosphere using dry boxtechniques. All solvents used were HPLC grade and were dried beforetheir use.

MMAO

refers to modified methylalumoxane, a triisobutylaluminum modifiedmethylalumoxane available commercially from Akzo-Nobel Corporation.

The preparation of catalyst (A5) is conducted as follows.

The bis-imine,3-(2,6-diisopropylphenylimino)butan-2-ylidene-2,6-diisopropylbenzenamine,is synthesized according to procedures published in WO2003/051935.

a) Synthesis ofN-(3-(2,6-diisopropylphenylamino)-3-methylbutan-2-ylidene)-2,6-diisopropylbenzenamine

In a nitrogen-filled glovebox, the above referenced bis-imine (6.48 g,16.0 mmol) is dissolved in toluene (50 mL) and trimethylaluminum (9.61mL, 19.2 mmol) is added dropwise. After stirring for one hour at roomtemperature, the reaction mixture is removed from the glovebox, andwater (10 mL) is added very slowly under nitrogen purge. The mixturebubbles violently, and the color slowly turns from yellow to colorlessas a white precipitate develops. The mixture is filtered to removeinsoluble aluminum salts. The organic layer from the filtrate isseparated and the aqueous layer is washed with ether (100 mL). Thecombined organic fractions are dried over MgSO₄ and filtered, thenvolatiles are removed in vacuo to yield 6.55 g (73.6%) of a colorlesssolid.

b) Synthesis of 3-(2,6-diisopropylphenylamino)-3-methylbutan-2-one

The product of the previous reaction (17.45 g, 41.5 mmol) is dissolvedin ethanol (200 mL). Water (65 mL) is added, precipitating a whitesolid. Over a 60 minute period, sulfuric acid (1.0 M, 150 mL, 150 mmol)is added via dropping funnel while stirring the reaction mixture. Duringthe reaction, the solid dissolves to form a pale yellow solution, whichis heated at reflux temperature for one hour, then allowed to cool toroom temperature. Potassium hydroxide pellets (˜20 g) are added slowly,while monitoring pH. Just after the endpoint (pH ˜11), the product isextracted with ether (2×150 mL), washed with brine, dried over MgSO₄,and filtered. As the solvent is removed by evaporation, a whiteprecipitate forms. This is collected and washed with cold pentane.Yield=1.75 g. The remaining solution is dissolved in pentane (100 mL),washed with brine to remove residual water, dried over MgSO₄, filteredand evaporated to about 30 mL. Additional white solid precipitates uponcooling. Yield=1.41 g. Total yield=3.16 g (29.1%).

c) Synthesis of2,6-diisopropyl-N-(2-methyl-3-(octylimino)butan-2-yl)benzenamine

The product of the previous reaction (1.500 g, 5.74 mmol) is dissolvedin toluene (15 mL) in a 25 mL round-bottom flask, and octylamine (1.00mL, 6.03 mmol) is added. A very small amount (ca 1 mg) ofp-toluenesulfonic acid is added and the mixture is heated at refluxtemperature with a Dean-Stark condenser attached. After heatingovernight, additional n-octylamine (2.00 mL, 12.1 mmol) is added and thereaction mixture is further heated to effect complete conversion. Water(5 mL) is added. The organic layer is separated, dried over MgSO4,filtered and then volatiles evaporated. 1.62 g (75.8%) of colorlessviscous liquid is collected.

In a nitrogen-filled glovebox, the imino-amine ligand (5.548 g, 14.89mmol) is dissolved in toluene (80 mL), and n-BuLi (1.6 M in hexanes,10.2 mL, 16.4 mmol) is added. The clear yellow solution is stirred atroom temperature for one hour, and then HfCl₄ (4.769 g, 14.89 mmol) isadded. After stirring at room temperature for six hours, MeMgBr (3.0M inether, 16.4 mL, 49.1 mmol) is added. Stirring is continued overnight asthe color slowly progresses from light yellow to dark brown. Volatilesare removed from the reaction in vacuo, and hexanes (100 mL) are added.The mixture is stirred for 30 minutes, filtered and the solids arewashed with additional hexanes (100 mL). Solvents are removed from thecombined filtrates in vacuo to yield a light tan solid. Yield=6.472 g(73.0%).

Cocatalyst 1

A mixture of methyldi(C₁₄₋₁₈alkyl)ammonium salts oftetrakis(pentafluorophenyl)borate (here-in-after armeenium borate),prepared by reaction of a long chain trialkylamine (Armeen™ M2HT,available from Akzo-Nobel, Inc.), HCl and Li[B(C₆F₅)₄], substantially asdisclosed in U.S. Pat. No. 5,919,9883, Ex. 2.

Cocatalyst 2

Mixed C₁₄₋₁₈ alkyldimethylammonium salt ofbis(tris(pentafluorophenyl)-alumane)-2-undecylimidazolide, preparedaccording to U.S. Pat. No. 6,395,671, Ex. 16.

Shuttling Agents

The shuttling agents employed include diethylzinc (DEZ, SA1),di(i-butyl)zinc (SA2), di(n-hexyl)zinc (SA3), triethylaluminum (TEA,SA4), trioctylaluminum (SA5), triethylgallium (SA6), i-butylaluminumbis(dimethyl(t-butyl)siloxane) (SA7), i-butylaluminumbis(di(trimethylsilyl)amide) (SA8), n-octylaluminumdi(pyridine-2-methoxide) (SA9), bis(n-octadecyl)i-butylaluminum (SA10),i-butylaluminum bis(di(n-pentyl)amide) (SA11), n-octylaluminumbis(2,6-di-t-butylphenoxide) (SA12), n-octylaluminumdi(ethyl(1-naphthyl)amide) (SA13), ethylaluminumbis(t-butyldimethylsiloxide) (SA14), ethylaluminumdi(bis(trimethylsilyl)amide) (SA15), ethylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide) (SA16), n-octylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide) (SA17), n-octylaluminumbis(dimethyl(t-butyl)siloxide(SA18), ethylzinc (2,6-diphenylphenoxide)(SA19), and ethylzinc (t-butoxide) (SA20).

Examples 1-16 Comparative Examples A, B, E and F

Continuous solution polymerizations are carried out in a computercontrolled autoclave reactor equipped with an internal stirrer. Purifiedmixed alkanes solvent (Isopar™ E available from ExxonMobil ChemicalCompany), ethylene at 2.70 lbs/hour (1.22 kg/hour), propylene, andhydrogen (where used) are supplied to a 3.8 L reactor equipped with ajacket for temperature control and an internal thermocouple. The solventfeed to the reactor is measured by a mass-flow controller. A variablespeed diaphragm pump controls the solvent flow rate and pressure to thereactor. At the discharge of the pump, a side stream is taken to provideflush flows for the catalyst and cocatalyst and SA1 injection lines andthe reactor agitator. These flows are measured by Micro-Motion mass flowmeters and controlled by control valves or by the manual adjustment ofneedle valves. The remaining solvent is combined with propylene,ethylene, and hydrogen (where used) and fed to the reactor. A mass flowcontroller is used to deliver hydrogen to the reactor as needed. Thetemperature of the solvent/monomer solution is controlled by use of aheat exchanger before entering the reactor. This stream enters thebottom of the reactor. The catalyst component solutions are meteredusing pumps and mass flow meters and are combined with the catalystflush solvent and introduced into the bottom of the reactor. The reactoris run liquid-full at 500 psig (3.45 MPa) with vigorous stirring.Product is removed through exit lines at the top of the reactor. Allexit lines from the reactor are steam traced and insulated.Polymerization is stopped by the addition of a small amount of waterinto the exit line along with any stabilizers or other additives andpassing the mixture through a static mixer. The product stream is thenheated by passing through a heat exchanger before devolatilization. Thepolymer product is recovered by extrusion using a devolatilizingextruder and water cooled pelletizer. Process details and results arecontained in Table 1. For comparative examples A, B, E and F noshuttling agent was introduced into the reactor.

Selected polymer properties are provided in Table 2. Comparative ExampleC is Paratone 8941 (ExxonMobil Chemical Co.) and Comparative Example Dis Nordel IP 225 (The Dow Chemical Company).

TABLE 1 Process details for preparation of exemplary polymers Cat DEZCat A1 Cat A5 Conc DEZ Cocat Cocat Poly C₂H₄ C₃H₆ Solv. H₂ T A1 ² FlowA5 ³ Flow ppm Flow Conc. Flow [C₂H₄]/ Rate ⁵ Conv Solids Ex. kg/hr kg/hrkg/hr sccm ¹ ° C. ppm kg/hr ppm Kg/hr Zn kg/hr ppm kg/hr [DEZ] ⁴ kg/hr %% Eff. ⁷ A * 1.48 1.5 10.5 109.9 120.0 64.2 0.090 19.8 0.198 — — 573.70.065 — 1.2 85.1 9.2 0.17 B * 1.04 1.4 10.0 99.9 100.0 19.8 0.055 61.10.019 — — 427.3 0.040 — 1.2 92.0 9.2 0.51 E * 1.04 1.5 22.0 2.1 100.019.8 0.168 18.9 0.038 — — 427.3 0.069 — 1.2 89.4 9.2 0.33 1 1.48 1.5 100.0 119.9 64.2 0.090 19.8 0.197 4001 0.105 573.7 0.058 1027.3 1.2 83.79.2 0.17 2 1.04 1.3 10.0 1.0 99.8 19.8 0.067 61.1 0.023 3017 0.102 427.30.051 767.6 1.2 90.2 9.1 0.42 3 1.04 1.3 10.0 1.0 100.0 19.8 0.066 61.10.023 3017 0.073 427.3 0.051 1158.5 1.1 89.5 9.1 0.42 4 1.28 1.3 12.089.9 100.0 19.2 0.023 51.9 0.112 2431 0.045 946.4 0.052 1523.8 1.5 93.113.2 0.24 5 1.05 1.7 9.9 0.0 120.0 53.1 0.013 59.2 0.253 3030 0.104 ⁸ ⁸536.9 3.7 92.9 — 0.30 6 1.05 1.8 10.0 0.0 120.0 53.1 0.017 59.2 0.2303030 0.100 ⁸ ⁸ 907.3 3.2 88.8 — 0.25 7 1.09 1.8 10.0 43.3 120.0 53.10.018 59.2 0.229 3030 0.052 ⁸ ⁸ 1478.8 3.5 90.5 — 0.26 8 1.00 1.6 10.10.0 120.0 53.1 0.018 59.2 0.229 3030 0.102 ⁸ ⁸ 873.9 3.2 89.4 — 0.29 91.08 1.8 9.7 0.0 120.0 53.1 0.018 59.2 0.230 3030 0.097 ⁸ ⁸ 633.6 3.692.0 — 0.23 10 1.02 1.7 10.0 0.0 119.9 53.1 0.025 59.2 0.209 3030 0.098⁸ ⁸ 893.1 3.3 89.5 — 0.21 11 1.04 1.5 22.0 2.5 100.1 19.8 0.161 18.90.041 3017 0.096 427.3 0.067 863.7 1.2 89.7 9.4 0.34 12 1.04 1.5 22.02.1 99.9 19.8 0.175 18.9 0.040 3017 0.150 427.3 0.070 598.9 1.2 88.9 9.50.30 13 1.04 2.1 22.0 2.4 100.0 19.8 0.139 18.9 0.063 3017 0.096 427.30.062 962.2 1.1 88.5 8.5 0.34 F * 0.87 1.4 15.2 110.9 100.0 13.4 0.10313.0 0.184 — — 427.3 0.079 — 1.05 88.9 5.9 0.284 14 0.87 1.4 15.2 73.9100.0 13.4 0.114 13.0 0.218 990.8 0.046 382.4 0.091 4615 1.09 89.6 6.10.258 15 0.87 1.4 15.2 58.6 100.0 13.4 0.111 30.4 0.091 990.8 0.084382.4 0.088 2531 1.09 89.5 6.1 0.257 16 0.87 1.4 15.2 3.0 100.0 13.40.108 30.4 0.089 1987 0.077 382.4 0.086 1371 1.09 89.7 6.1 0.262 *Comparative, not an example of the invention ¹ standard cm³/min ²[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl ³[η²-2,6-diisopropyl-N-(2-methyl-3-(octylimino)butan-2-yl)benzenamide]trimethylhafnium⁴ molar ratio in reactor ⁵ polymer production rate ⁶ percent ethyleneconversion in reactor ⁷ efficiency, kg polymer/mg M where mg M = mg Hf(A1) + mg Hf (A5) ⁸ A Cocat/(Cat A1 + Cat A5) molar ratio of 1.2 wasmaintained.

FTIR measurements were made using according to ASTM D-3900-05 toestimate the total weight percent of ethylene present. Alternatively,the measurement could also be made by NMR.

T_(m) vs wt % C₂

When the inventive polymers comprise a majority of hard segments, theyhave melting temperatures that are higher than those of comparativerandom copolymers for a given weight percent of ethylene, based on theweight of the polymer. A calibration line may be obtained for any givencomonomer. This relationship for propylene as a comonomer is shown inFIG. 1, wherein it can be seen that the numerical values for the melttemperatures for a given weight percent ethylene have the followingrelationship:Tm≧4.1276(wt % C ₂)−244.76.Table 3 shows the data corresponding to FIG. 1.

TABLE 3 Example T_(m) Wt % C₂ 1 70.25 71.4 A* 62.3 71.7 2 45 71 3 37 71B* 39 70.9 11  38 66.5 E* 58 67.1 12  48 65 4 65 69 *Comparative, not anexample of the inventionWhen the inventive polymers comprise a majority of soft segments, theyhave melting points that are lower than those of comparative randomcopolymers for a given weight percent of ethylene, based on the weightof the polymer. This relationship for propylene as the comonomer isshown in FIG. 2, wherein it can be seen that the numerical values forthe melt temperatures for a given weight percent ethylene have thefollowing relationship:Tm≦4.1276(wt % C ₂)−264.95.

TABLE 4 Example T_(m) Wt % C₂ 6 −9.9 64.9 7 −15.8 64.6 8 1.5 67.7 9−20.8 61.8 10 −6.5 66.9 5 −16.1 62.8

Methods for Targeting the Composition in Inventive Examples

The block architecture of the exemplary OBC's is controlled by theproper selection of catalysts to produce the desired propylene contentin each of the segments at the reactor conditions. The amount ofcomonomer incorporated into each segment type can be predicted byindependently performing polymerization tests employing singlecatalysts. Thus, the ratio of propylene to ethylene concentrations inthe reactor ([C3]/[C2]) determines the amount of propylene (relative toethylene) incorporated by each catalyst. Upon introduction of the chainshuttling agent, a ‘blocky’ structure is produced by statisticalcoupling of the polymer segments produced by each catalyst type. Thetotal comonomer incorporated into the polymer is then controlled by theratio of catalyst A₁ to catalyst A₂. This concept of production andmethodology is explained in Arriola et al., “Catalytic Production ofOlefin Block Copolymers via Chain Shuttling Polymerization”, Science,312 (2006).

From the above methodology, the wt % ethylene or propylene incorporatedinto the polymer by catalyst A1, the wt % ethylene or propyleneincorporated into the polymer by catalyst A2, and the amount of polymerproduced by each of the catalysts can be estimated from the reactorconditions and the overall comonomer content of the polymer.

The total/overall monomer or comonomer incorporated into the polymer canbe estimated as follows:Overall Comonomer Incorporated=M _(Overall) =X _(A) M _(A) +X _(B) M_(B)

Where

M_(Overall)=Overall wt % C2 incorporated in whole polymer

M_(A)=wt % C2 incorporated in segment by Catalyst A1

M_(B)=wt % C2 incorporated in segment by Catalyst A2

X_(A)=weight fraction of segment produced by Catalyst A1

X_(B)=weight fraction of segment produced by Catalyst A2

Note: X_(A)+X_(B)=1

Using the total monomer or comonomer incorporated into the polymer asmeasured by FTIR or NMR, and knowing the comonomer concentration of eachsegment type in the reactor at the time of production, the weightfraction of polymer produced by each catalyst can be determined.

Weight fraction of segment produced by Catalyst A1

$X_{A} = \frac{M_{Overall} - M_{B}}{M_{A} - M_{B}}$

Weight fraction of segment produced by Catalyst A2 X_(B)=1−X_(A)

Other analytical methods to confirm the composition of the segmentscomprise DSC, NMR, and the subsequent analysis of polymer fractionsobtained by polymer fractionation (temperature fractionation, solventfractionation, molecular weight fractionation). Additionally, atechnique such as high temperature liquid chromatography as described inAlbrecht et al. “Separation and Charactierization of Ethylene-PropyleneCopolymers by High-Temperature Gradient HPLC Coupled to FTIRSpectroscopy”, Macromol. Symp., 257, 46-55 (2007) could also be used.For any of these methods, the composition of the exemplary blockcopolymers can be estimated with the appropriate calibrations based onthe random copolymers produced by a similar catalyst system and withinthe same range of molecular weights and overall compositions.

TABLE 5 Targeted Block Copolymer Compositions of exemplary polymersEthylene Ethylene Wt % C2 Wt % C2 Wt Hard % (wt %) (wt %) IncorporationIncorporation polymer made Ex. FTIR NMR for Cat A1¹ for Cat A2² from CatA1¹ A* 71.7 — — — 40 B* 70.9 — 75 58 70 C* 62.4 — NA NA NA D* 70.5 — NANA NA E* 67.1 — 75 58 50 1 71.4 — — — 40 2 71.5 — 75 58 70 3 71.2 — 7558 70 4 69.0 — 75 58 65 5 62.8 — — — 15 6 64.9 — — — 22 7 64.6 — — — 228 67.7 — — — 22 9 61.8 — — — 22 10 66.9 — — — 30 11 66.5 — 75 58 50 1266.8 — 75 58 50 13 62.3 — 75 58 50 F* 69.7 71.1 75 58 65 14 68.8 68.7 7558 65 15 69.0 69.0 75 58 65 16 69.6 70.0 75 58 65¹[N-(2,6-di(1-methylethyl)phenylamido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl²[η²-2,6-diisopropyl-N-(2-methyl-3-(octylimino)butan-2-yl)benzenamide]trimethylhafniumGPC-IR and Turbidity Measurements

Ethylene content throughout the GPC curve was monitored via GPC-IR. Thenumerical values of the ethylene content in wt % ethylene based onweight of polymer vs molecular weight fractions were plotted and fittedto a line, m×+b. The absolute slope, |m|, and turbidities in oil anddodecane are given in Table 4 below. As may be seen, for the inventivepolymers, |m| is less than 4 and the turbidity is equal to or less thanthat of a polymer with a comparable DSC enthalpy, J/g, at greater than55° C., ΔH_(>55° C.), within ±5 J/g. An example of GPC-IR plots withcorresponding lines and equation giving the slope, m, is given in FIG.3. Turbidity in oil is measured for a 1 wt % solution of polymer, basedon the weight of oil and turbidity in dodecane is measured for a 1.5 wt% solution of polymer, based on the weight of dodecane.

TABLE 6 Ex. ΔH_(>55° C.) |m| Turbidity (oil) Turbidity (dodecane) A* 1810.1 10.5 20 B* 5.3 5.1 2.1 6.5 C* 2.4 6.3 3.1 2.4 D* NM 1.3 NM NM 118.5 2.9 2.9 11.8 2 9.9 2.4 1.8 2 3 5.2 NM 2.9 NM 4 10.4 0.54 2.5 6.7 60.4 NM 0.8 NM 5 0.8 NM 0.7 NM 7 NM NM NM NM 8 0.5 NM NM NM 9 0 NM NM NM11  1.3 0.94 1.5 NM E* 4.2 7.2 2.7 NM 12  1.1 NM 1.1 NM 13  0 NM 1.0 NM*Comparative, not an example of the invention

While the invention has been described with respect to a limited numberof embodiments, the specific features of one embodiment should not beattributed to other embodiments of the invention. No single embodimentis representative of all aspects of the invention. In some embodiments,the compositions or methods may include numerous compounds or steps notmentioned herein. In other embodiments, the compositions or methods donot include, or are substantially free of, any compounds or steps notenumerated herein. Variations and modifications from the describedembodiments exist. Finally, any number disclosed herein should beconstrued to mean approximate, regardless of whether the word “about” or“approximately” is used in describing the number. The appended claimsintend to cover all those modifications and variations as falling withinthe scope of the invention.

What is claimed is:
 1. An ethylene/α-olefin interpolymer comprising ahard segment and a soft segment, wherein the ethylene/α-olefininterpolymer: (a) has a Mw/Mn from about 1.7 to about 3.5; (b) has anethylene content in the hard segment in the range of from 70 wt % to 85wt % based on total monomer content in hard segment; (c) (i) has a hardsegment composition of at least 40%, at least one melting point, Tm, indegrees Celsius and an amount of ethylene in weight percent, wt % C₂based on total weight of the polymer, wherein the numerical values of Tmand wt % C₂ correspond to the relationship:90° C.≧Tm≧4.1276(wt % C ₂)−244.76; or (ii) has a hard segmentcomposition of less than 40%, at least one melting point, Tm, in degreesCelsius and an amount of ethylene in weight percent, wt % C₂ based ontotal weight of the polymer, wherein the numerical values of Tm and wt %C₂ correspond to the relationship:80° C.≧Tm≦4.1276(wt % C ₂)−264.95; or (iii) is characterized by anaverage block index greater than zero and up to about 1.0; or (iv) has amolecular fraction which elutes between 0° C. and 130° C. whenfractionated using low temperature TREF, characterized in that thefraction has a molar comonomer content of at least 5 percent higher thanthat of a comparable random ethylene interpolymer fraction elutingbetween the same temperatures, wherein said comparable random ethyleneinterpolymer has the same comonomer(s) and has a melt index, density,and molar comonomer content (based on the whole polymer) within 10percent of that of the ethylene/α-olefin interpolymer; or (v) has arelationship between ethylene content in wt % and log molecular weightsuch that a line plotted of ethylene content vs log molecular weight asmeasured by GPC-IR has an absolute slope, m, of equal to or less than 4;and, (d) has a turbidity measurement of a 1.0 wt % solution of theethylene/α-olefin interpolymer in oil or a 1.5 wt % solution in dodecaneof less than or equal to that of a comparable copolymer wherein thecomparable copolymer has the same DSC enthalpy (J/g) at greater than 55°C. within ±5 J/g, and the same overall ethylene content within 10%; and,wherein the soft segment comprises 35 wt % to 80 wt % comonomer based ontotal monomer content in the soft segment.
 2. The ethylene/α-olefininterpolymer of claim 1 comprising ethylene in an amount in the range offrom about 55 wt % to about 75 wt % based on total weight of thepolymer.
 3. The ethylene/α-olefin interpolymer of claim 1 comprisingethylene in an amount in the range of from about 60 wt % to about 73 wt% based on total weight of the polymer.
 4. The ethylene/α-olefininterpolymer of claim 1 having a T_(m) in the range of from about −25°C. to about 100° C.
 5. The ethylene/α-olefin interpolymer of claim 1having a T_(m) in the range of from about 30° C. to about 80° C.
 6. Theethylene/α-olefin interpolymer of claim 1 having a T_(m) in the range offrom about 35° C. to about 75° C.
 7. The ethylene/α-olefin interpolymerof claim 1 having a T_(m) that is less than that of a comparable randomcopolymer having a total weight percent comonomer within 10 wt % of thatof the ethylene/α-olefin interpolymer.
 8. The ethylene/α-olefininterpolymer of claim 1 having a turbidity in a 1.0 wt % solution of theethylene/α-olefin interpolymer in oil or a 1.5 wt % solution in dodecanethat is less than 1.5 NTU and a DSC enthalpy at greater than 55° C. ofless than 2 J/g.